The Longitudinal Aging Study in India (LASI) is a multidisciplinary, internationally harmonized panel data set that is designed to be representative of the elderly population in India. A pilot study has been funded by the National Institute on Aging (1R21AG032572-01) and will be fielded in November 2010. LASI will collect information that is conceptually comparable to that of the Health and Retirement Study (HRS) and its NIA-funded sister surveys in Asia. The survey will also collect dried blood spot (DBS) specimens that can be analyzed subsequently for different biomarkers. DBS analyses are particularly important in assessing the extent of undiagnosed diseases in countries like India, where lower education levels and limited access to medical care among the elderly often results in inaccurate self reports of health. However, there is currently no funding available for the DBS-based bioassays. Moreover, while the laboratories in India have the infrastructure to conduct standard enzyme linked immunosorbent assays (ELISA) and the experience to detect human immunodeficiency virus (HIV) antibody in DBS samples, they have underdeveloped capacity to measure other DBS-based biomarkers. Therefore, the specific aims of this application are: (a) to further develop laboratory capacity to conduct DBS-based bioassays in India; (b) to measure C-reactive protein (CRP, a marker of inflammation), glycosylated hemoglobin (HbA1c, a marker of glucose metabolism), hemoglobin (Hb, a marker of anemia), and Epstein-Barr virus (EBV) antibodies (a marker of cell-mediated immune function) from DBS specimens; (c) to validate CRP, HbA1c, Hb, and EBV antibody measurements on DBS by comparing similar assays done in India and the United States, and by comparing test results from DBS with matched venous blood samples in India; (d) to analyze and link these new biomarker data to the extensive socioeconomic status and self-reported health information, and to the anthropometric and biometric parameters that will be collected or measured during the LASI pilot survey; and (e) to disseminate the measured assay data, which are linked to the LASI pilot data, and the detailed information about laboratory procedures, to the international scientific community via the LASI website.